1. Field of the Invention
The present invention relates to a slide rail device, for a vehicle, which supports a seat in a slidable manner.
2. Description of Related Art
A slide rail device for a vehicle which is disclosed in Japanese Unexamined Patent Application No. 2011-230717 is provided with a pair of left and right lower rails extending in a forward/rearward direction (of the vehicle) and fixed to a floor of the vehicle; a pair of left and right upper rails which support a seating portion of a seat and are slidably supported by the pair of left and right lower rails; a lock mechanism provided between the upper rails and the lower rails which restricts the sliding movement of the upper rails and releases sliding movement restriction of the upper rails; a pair of left and right lock-operation levers (lock-release levers) which are respectively inserted inside the upper rails and each are open at the front end and lower end thereof; and a loop handle, the left and right rear ends of which are inserted into the front end internal spaces of the left and right lock-operation levers, respectively. The lock-operation levers are each upwardly and downwardly rotatable between a locked position at which a sliding movement restriction, via the lock mechanism, of the upper rails is allowed, and a unlocked position at which the sliding movement restriction is released by moving the front ends of the lock-operation levers upward from the locked position.
Furthermore, this slide rail device is provided with a torsion spring formed from spring wire and attached to the front end internal space of each lock-operation lever. The torsion spring is first attached to the internal space (surface) of each lock-operation lever before the loop handle is attached to each lock-operation lever, and is immovable in the forward/rearward and upward/downward directions relative to the lock-operation lever due to the torsion spring itself engaging with the lock-operation lever at a plurality of locations. After the torsion spring is assembled into the front end internal space of each lock-operation lever, when each end portion of the loop handle is inserted into the internal space of each respective lock-operation lever from the front end of each respective lock-operation lever, the torsion spring supports the rear ends of the loop handle by being engaged with the rear ends of the loop handle.
When an occupant is not operating the loop handle, the upper rail is prevented from sliding relative to the lower rail by the lock mechanism provided therebetween. Whereas, if the occupant rotates the loop handle upwardly, the lock-operation lever that was positioned at the locked position rotates to the unlocked position, and since the slide-prevention of the lock mechanism is released, the upper rail becomes slidable relative to the lower rail.
The above-described slide rail device for a vehicle that is disclosed in Japanese Unexamined Patent Application No. 2011-230717 has a structure in which the torsion spring is assembled into the front end internal space of the lock-operation lever before the loop handle is attached to the lock-operation lever. However, in order to attach the torsion spring into the internal space of the lock-operation lever, it is necessary to elastically deform the torsion spring and engage the plurality of engaging portions thereof with corresponding engaging portions of the lock-operation lever. Therefore, assembling the torsion spring into the lock-operation lever is difficult. Accordingly, it is difficult to carry out a rapid assembly operation of the slide rail device for a vehicle.